


a lesson in xenopsychology

by LunDiiVith



Series: an unearthly child [1]
Category: Warhammer 40.000, Warhammer 40k (Novels) - Various Authors
Genre: Gen, Incest shippers dni, also some other characters who didn't have ao3 tags, but i feel like i lay it out fairly obviously, can you believe it, incest shippers do not interact, one of those short stories where you need to guess what's ACTUALLY going on
Language: English
Status: Completed
Published: 2021-01-19
Updated: 2021-01-19
Packaged: 2021-03-18 02:00:38
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,632
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28859229
Author URL: https://archiveofourown.org/users/LunDiiVith/pseuds/LunDiiVith
Summary: The Library of Ptolemy is no place for a child to be; is he lost?
Relationships: Cato Sicarius & Original Character
Series: an unearthly child [1]
Series URL: https://archiveofourown.org/series/2119572
Comments: 4
Kudos: 9





	a lesson in xenopsychology

**Author's Note:**

> I promise the next chapter of Finally Awake is coming soon, this is just an idea I had to scribble on the side while writing it, hahah.
> 
> Before you read this fic, I do want to ask you, the readers, for a favor? If that's possible. When you finish it, please don't compare it or its characters to other existing fics or its original characters. I'm aware of the similarities, but I have my own personal reasons to not want to hear about other fics featuring these characters. Sorry :(

The first time the man and the child meet, it’s in the Fortress of Hera’s Library of Ptolemy, and the man assumes the child is lost.

He’s looking through the Library’s tomes on xeno species, looking for some information in particular, when he sees the boy in the corner. A cane leans against the side of the wall, and sitting on the floor by it, reading an oversized book, is a kid, no older than ten, with light brown skin and long dark brown hair. His hands holding up the book have thin golden rings, ones the man faintly remembers seeing before on others. He’s so caught up in whatever he’s learning about that he hasn’t even seen the man, and the man is certainly not the stealthiest. Superhuman physique, of course, aside.

“Hello there,” the man finds himself saying. “Are you lost?”

Pilgrims have still been coming to the site where Roboute Guilliman once sat, albeit less than before. It’s not unreasonable to assume one of the children brought along for the ride has sneaked off, though it surprises him that he headed for the Library and not to watch the Astartes train. Isn’t it a common childhood dream, to join their ranks? An impossible dream, but kids have many of those; it’s part of a healthy childhood.

The child startles, surprised by the sudden noise, and looks up at the man. It’s quite a height gap, but he manages a glance nonetheless before giving up and just looking at the man’s shoes. Does he not recognize him? Interesting.

“No,” he says, very quietly and softly. “I’m waiting for my big brother.”

“Your brother?” The man turns around fully from the shelves, though not yet putting away the books he’s been meaning to read. It’s been some time since he met a kid who wasn’t a little scared of him up close, and he doesn’t blame them, but it’s interesting that this boy seems almost used to his sort. And, well, he’ll admit it; he’s soft-hearted when it comes to children. He can spare a few minutes to look after him, make sure nothing happens while he waits.

The boy touches his own too-long bangs. “He thought I’d like to go to a library, instead of him bringing me books,” he says. “And he said, since there’s one right here, I could stay there while he did his. Thing.” He frowns. “Forgot the word. But what he came here to do.”

_Pilgrimage_ isn’t a word most nine-year-olds have in their vocabularies; it was in the man’s, but he wasn’t a normal nine-year-old, and he’s fairly sure he knows where his life differs from the average human’s. “And he left you here?” the man inquires; if the brother’s adult, he might have some words with him.

“I can take care of myself,” the kid says, in that way only children have of saying such self-assured things because they think they know everything. “And it’s only supposed to be for a little bit. I’m not supposed to be away from any of my brothers for too long.”

_Brothers, plural?_ “How many brothers do you have, child?”

“A bunch. My dad has a lot of sons,” the child says. 

“And do you like them?” and the man smiles his warmest, most child-friendly smile. The boy nods slowly. 

“Yes,” he says, “if they’re nice to me. Some of them aren’t.” The man’s concerned by that comment, but files it away; he doubts he’ll see the child again. The boy then lifts the book closer to his chest, and silver letters on the black leather spine gleam for a moment.

“Oh, what are you reading?” Children usually love to be asked about their interests, don’t they? Maybe he’ll talk more about this.

“Oh— uhm…” The boy freezes. “I dunno, I just found it,” he mumbles, and he’s obviously lying; he was too engrossed in the book for it to have just been something he randomly picked up. “I’ll probably get another book soon, I’m not sure if I like it.” Children’s secrets are too petty for the man, but he can’t stop himself from chuckling internally. They always think they can get away with it.

“And what do you like to read, then?” the man continues asking, as gentle as he can be.

“About the stars,” the kid immediately says. “A-and about… I like physics. Did you know nothing actually touches? Like uhm. We’re all like, mostly just bits of stuff with empty space in between and so we have this like, protective bit, so we don’t go through each other…”

There they go. The boy keeps rattling off childish trivia about the fundamental laws of physics for a few minutes, and the man listens intently all the while, while checking the books he’s picked out to see if they’re the right ones. They are, and he waits for a little bit further before interrupting the child…

“...and the thingys need to be watched, because if they’re not watched they do all kinds of weird stuff that contradicts, and—”

“Child, when’s your brother picking you up?”

“O-oh, uhm. What time is it?” His eyes widen. The child half-clasps his hands in alarm — without interlacing his fingers, just grabbing one hand with the other, the man notices — and lets the book fall on his lap.

“Half past five, I believe.” 

“Then in— five minutes? I should, I should put this back,” the kid says. He reaches for his cane, but the man simply kneels to pluck the book from the child’s lap and puts it back on the shelf. He catches a glimpse of the title and frowns for a split second, confused; it deals with xenobiology. A strange topic for a child to be interested in. “A-ah, thank you!” the kid tells him.

The man kneels before the boy. “Unfortunately, I must leave now, but I appreciate what you’ve told me about physics,” he tells him, a small smile on his face. Now that he can see the child’s face properly, he can see a large pale birthmark under his eye, and another one near his mouth. His bangs can’t quite cover his eyes, which are an unearthly purple, like the scion of an astronomically rich family who’s paid to have their genes edited. And he still can’t recognize him? Well, the child might just be too young to have learnt about him… “I’d like to know the name of whoever taught me these things, though, so I know who to credit when I tell my men,” he adds. Children like to feel special.

“O-oh! Uhm,” the kid stutters. “I’m— My name’s Liyan. B-but it’s okay if you just tell your friends you read this somewhere!”

The man chuckles warmly. “If you say so,” he says, and he reaches forward to tousle Liyan’s hair, but the kid pulls away with an _eep!,_ and so the man retires his hand. “I hope we see each other again,” he adds, even though he knows he likely won’t, and he steps up and away from the child.

“W-wait! Sir!” the kid shouts without moving. “What’s your name?”

“Ask your brother,” the man tells him, “he’ll likely tell you! And tell him I think he shouldn’t leave children alone while he prays!”

The man leaves the library, already having informed its keepers what books he’ll take to his guest quarters; as he leaves, he nearly bumps into an unhelmeted Ultramarine. Ah— brown beard, light skin and that armor… the man recognizes him quickly.

Cato Sicarius, meanwhile, looks at him with surprise. “Lord Vulkan, I didn’t know you’d be in the Library today!”

The freshly-returned Primarch of the 18th Legion smiles at his nephew. “I had some free time once I was done responding to my sons’ fussy messages,” he says. “You shouldn’t be too surprised. I already told my brother, my business here is mostly an excuse to see him again after all this time.”

“I see,” Sicarius says, but there’s still clearly something bothering him. Vulkan won’t press him on it, though.

“Say,” the Primarch begins instead, instantly drawing Sicarius’s attention. “Out of those pilgrims seeking to pray where my brother laid… Has any of them been a family of two or more brothers? One of them a child, if that helps.”

“Hm? I’m not sure, my lord,” Sicarius admits. “I’ve been busy. If it’s not too much— why do you ask?”

“No reason,” Vulkan replies, “there was just a lost child at the Library, and I thought I’d warn you.”

“A… lost child?”

“He had long hair and a cane,” Vulkan elaborates, briefly miming long locks over his shoulder. “He said his brother would pick him up soon, but I just thought I’d warn you. Imagine if he’d gotten hurt.”

“Oh. I see, my lord.” Sicarius hesitates for a moment. “Did he say what his name was?”

“He didn’t tell me his surname, and I didn’t think it’d be appropriate to ask,” Vulkan tells him, “but he did mention his first name was Liyan. I’ll never get used to Imperial citizens naming their children after my brothers,” he adds, faux-conspiratively; but Sicarius misses it, a thoughtful look in his eyes.

“Thank you for telling me, my lord,” Sicarius says. “I’ll— I’ll ask later for his family.” He bites his lip; a tell. He was lying about asking? Really, Roboute’s children have always been a little haughty. He’ll just tell Roboute about it again, then. “If that’s all…?” Sicarius adds, and Vulkan nods.

Vulkan leaves for his quarters, and on his way there, flips through the tomes he’s picked up from the Library. _The Unlikely Alliance_ ; _On the Mysterious Ynnari_ ; _Return of a Primarch_. _Let’s see if these aren’t censored_ , he thinks… _Roboute, what are you hiding from me?_

**Author's Note:**

> Liyan isn't derivated from Lion, it's short for something else. If you guess what in the comments, you get a virtual cookie, man's promise.
> 
> I might write more about him if folks like him! When the next FA chapter's done, I might write a little thing of him with his dad. It'd be cute, right?
> 
> You can learn more about my OCs on my [tumblr](https://luwupercal.tumblr.com)! ([Here's Liyan's tag](https://luwupercal.tumblr.com/tagged/oc-liyan)).
> 
> Once again: please don't compare him to other existing characters! Thank you very much!


End file.
